Streptomyces liangshanensis sp. nov., a novel actinomycete isolated from rhizosphere soil of Fagopyrum tataricum.

A novel actinomycete strain, designated strain QMT-12T, was isolated from the rhizospheric soils of Fagopyrum tataricum and characterized using a polyphasic approach. Strain QMT-12T was found to have morphological features typical of the genus Streptomyces. The predominant fatty acids included C18:1 cis9 (35.9%), Summed feature 6 (C18:2 cis9, 12/C18:0 a or C18:0 anteiso/C18:2 c) (30.6%) and C16:0 (16.3%). The whole-cell sugars were arabinose and glucose. The whole-cell-wall amino acids included alanine, aspartate, glutamic acid, glycine and LL-diaminopimelic acid. The menaquinones were MK-9, MK-9(H2), MK-9(H4), MK-9(H6) and MK-9(H8). The diagnostic phospholipids consisted of diphosphatidyl glycerol, phosphatidylethanolamine, phosphatidyl methyl ethanolamine, phospholipids, phosphotidyl inositol, phosphotidylinositol mannosides, and phospholipids of unknown structure containing glucosamine. The full-length 16S rRNA gene sequence analysis showed that strain QMT-12T belonged to the genus Streptomyces and had 98.2, 98.1, 98.1 and ≤ 98.0% similarities to Streptomyces camponoticapitis 2H-TWYE14T, Streptomyces scopuliridis NRRL B-24574T, Streptomyces inhibens NEAU-D10T and other Streptomyces species with validly published and correct names, respectively. Phylogenetic analysis indicated that strain QMT-12T was closely related to Streptomyces inhibens NEAU-D10T. However, the average nucleotide identity value and the digital DNA-DNA hybridization value between strain QMT-12T and S. inhibens NEAU-D10T were 85.0 and 22.3%, respectively, well below 95-96% and 70% cut-off point recommended for delineating species. Based on its phenotypic and genotypic characteristics, strain QMT-12T (= CICC 11056T = JCM 33963T) represents the type strain of a novel species, for which the name Streptomyces liangshanensis sp. nov. is proposed.